Auger-bit.



No. 762,099. PATENTED JUNE 7, 1904.

. N. SPBRRY.

AUGER BIT.

APPLICATION FILED MAR. 24. 1904.

N0 IODEL.

TM! NORRISPETZRSY cot. PHOTO-LITNO. WASHINGTON. n. c.

UNITED STATES Patented June '7, 1904.

PATENT OFFICE.

AUGER-BIT.

SPECIFICATION forming part of Letters Patent No. 762,099, dated June 7,1904.

Application filed March 24:, 1904.

To all whom it may concern:

Be it known that I, NORMAN SPERRY, of Seymour, in the county of NewHaven and State of Connecticut, have invented a new and usefulImprovement in Auger-Bits; and I do hereby declare the following, whentaken in connection with the accompanying drawings and the letters ofreference marked thereon, to be a full, clear, and exact description ofthe same, and which said drawings constitute part of this specification,and represent, in

Figure 1, aside view of the end of an angerbit constructed in accordancewith my invention; Fig. 2, a similar view turned half around; Fig. 3, anend or plan view.

This invention relates to an improvement in auger-bits, and particularlyto that class which include a spiral head ,or body, two floor-lips, witha gimlet-point. In bits of this character it is desirable that a coarsethread should be employed on the point in The head or body A of the bitis of usual spiral form, terminating in floor-lips B C, and

Serial No. 199,673. (No model.)

while the inner edge of the lip B merges into,

a thread H, which extends around the point F midway between the threadsG and dies out into the point about midway of its length. The thread Gat the lower portion of the point forms a coarse thread and gives therequired draw, while the thread H assists the thread G in givingsufficient out to the Wood and provides a cutting-thread for eachfloor-lip, thus giving all the practical advantages of a double-threadedpoint and the drawing qualities of a single thread. I

Having fully described my invention, What I claim as new, and desire tosecure by Letters Patent, is

An auger-bit comprising a body, two floorlips and a point, a threadextending from one floor-lip to the outer end of the point, and a threadextending from the other floor-lip between the other threads and dyingout above the outer end of the point, substantially as described.

In testimony whereof I have signed this specification in the presence oftwo subscribing witnesses.

NORMAN SPERRY. Witnesses:

FREDEEIc C. EARLE, CLARA L. WEED.

